Forty-nine studies were included in the review: four high-quality RCTs (n=160, range 26 to 60) that reported effectiveness; and 45 observational studies (five high quality, 33 medium quality, seven low quality, n=over 6,189, range 12 to 3,130) that reported adverse effects. Withdrawal rates ranged from nil to 42% where reported.
There was no statistically significant difference between intervention and control groups for any measure of daytime sleepiness (four RCTs pooled), quality of life (two RCTs) and apnoea-hypopnoea (three RCTs). One RCT (n=46) reported that LAUP significantly improved snoring intensity (VAS WMD -4.0, 95% CI -5.5 to-2.5) and frequency (WMD -3.6, 95% CI -1.3 to 15.9) compared to no treatment. A second RCT found no significant difference between LAUP and sham treatment for snoring measures. One RCT (n=26) reported that TCRAFTA significantly improved snoring (VAS WMD 2.5, 95% CI 0.4 to 4.6) compared to sham surgery.
Six studies (one high, two medium and four low quality, n=15,398) reported a total of 30 deaths after UPPP or LAUP, in most cases associated with respiratory compromise, bleeding, intubation problems, infection or cardiac arrest. One of these, a high-quality observational study (n=3,130) reported perioperative/postoperative death in 0.2% (95% CI 0.1 to 0.4) and other serious complications in 1.5% (95% CI 1.1 to 1.9) of patients after UPPP. There was moderate or strong evidence that both UPP (weighted mean 27%, range 19 to 29; six studies) and UPPP (weighted mean 31%, range 13 to 36; four studies) were associated with swallowing problems.
No significant statistical heterogeneity was evident. Other data on adverse effects were reported in the review.